Perhaps you should try some spelling variations:
hieu thien » hieu hien, chieu chien, dieu khien
thien hach » thien thanh, hien hanh
cau tren » cu tren, dau tren, ca tren
duoc va » nuoc va, duc va, duoc ma
cuu tre » cua tre, cau treo
xanh di » danh di, vanh dai, xanh tai
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
tuoc va » thuoc va, nuoc va, tuc va
nang xa » nang x, lang xa, nang ma

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky nang xa hoi. hieu thien hach ((tuoc va) or (duoc va)) xanh di ((cuu tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang xa hoi. hieu thien hach ((tuoc va) OR (duoc va)) xanh di ((cuu tre) OR (cau tren)).
• Adding a wildcard symbol may retrieve word variants: su sach ky nang xa hoi. hieu thien hach ((tuoc va) or (duoc va)) xanh di ((cuu tre) or (cau tren))*.